MK2058-01
Communications Clock Jitter Attenuator
Description
The MK2058-01 is a VCXO (Voltage Controlled Crystal
Oscillator) based clock jitter attenuator designed for
system clock distribution applications. This monolithic
IC, combined with an external inexpensive quartz
crystal, can be used to replace a more costly hybrid
VCXO retiming module. The device accepts and
outputs the same clock frequency in selectable ranges
covering 4kHz to 27MHz. A dual input mux is also
provided.
By controlling the VCXO frequency within a
phase-locked loop (PLL), the output clock is phase and
frequency locked to the input clock. Through selection
of external loop filter components, the PLL loop
bandwidth and damping factor can be tailored to meet
system clock requirements. A loop bandwidth down to
the Hz range is possible.
Features
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Excellent jitter attenuation for telecom clocks
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Also serves as a general purpose clock jitter
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attenuator for distributed system clocks and
recovered data or video clocks
2:1 Input MUX for input reference clocks
VCXO-based clock generation offers very low jitter
and phase noise generation
Output clock is phase and frequency locked to the
selected input reference clock
Fixed input to output phase relationship
+115ppm minimum crystal frequency pullability
range, using recommended crystal
Industrial temperature range
Low power CMOS technology
20 pin SOIC package
Single 3.3V power supply
Block Diagram
P u llable xtal
VD D
ISE T
X1
X2
VDD
3
In p ut C lock
In p ut C lock
IC LK 2
IC LK 1
1
0
Ph ase
D etecto r
C h arge
P um p
VC X O
Selectable
D ivider
C LK
IS EL
S EL 2:0
3
CHGP
V IN
GND
4
MDS 2058-01 B
1
Revision 071001
Integrated Circuit Systems, Inc.
q
525 Race Street, San Jose, CA 95126
q
tel (408) 295-9800
q
www.icst.com
ICS [ INTEGRATED CIRCUIT SYSTEMS ]
